A liquid crystal display device and an organic EL (Electroluminescence) display device are represented as an example of a display device. A liquid crystal display device and an organic EL display device respectively have, as a display element, a liquid crystal element and an organic light-emitting element (hereinafter, referred to as a light-emitting element) in each of a plurality of pixels formed over a substrate. A liquid crystal element and a light-emitting element respectively have a layer including a compound exhibiting liquid crystallinity and a layer (electroluminescence layer) including an emissive organic compound between a pair of electrodes (cathode and anode) and are operated by applying a voltage or supplying current between the electrodes.
Use of a flexible substrate as a substrate provides flexibility to a part of or the whole of the display device, allowing the formation of a flexible display which can be freely bent or folded by a user. For example, Japanese Patent Application Publication No. 2014-95745 discloses that thermally shrinkable films exhibiting anisotropy in a shrinking direction are placed over and under a display device in order to prevent spontaneous deformation of the display device. This structure inhibits spontaneous deformation of the display device even if a temperature is changed, and the display device can be arbitrarily deformed according to the user's purpose.